The present invention relates generally to magnetic resonance imaging (MRI) and, more particularly, to virtual planes used in MRI images.
Magnetic Resonance Imaging (MRI) systems have become ubiquitous. Such systems use strong magnetic fields and radio waves to produce clear and detailed two- and three-dimensional images of anatomical parts of a body. The resolution of such MRI systems makes them particularly useful for imaging anatomical structures such as the spine in order to examine the anatomy of the vertebrae that make up the spine, as well as the spinal cord and the spaces between the vertebrae through which nerves pass.
However, as one skilled in the art will recognize, the field of view of typical MRI systems is limited. As a result, in many circumstances, the object to be imaged (e.g., the spine) cannot be imaged completely during one scan. As a result, different parts of the spine are imaged separately to produce a series of ordered 3D volumes associated with each of these parts of the spine. As one skilled in the art will recognize, and as used herein, a 3D volume refers to a volume formed from a number of 2D images, such as images taken by an MRI system. FIG. 1A shows one illustrative example of how different parts of a spine may be imaged in multiple stages. Referring to that figure, image 101 is an image of the cervical vertebrae of a spine, image 102 is an image of the thoracic vertebrae of the spine, and image 103 is an image of the lumbar vertebrae of the spine. Once obtained for each part of the spine, then these separate ordered volumes are composed into a single comprehensive volume, such as image 104 in FIG. 1B, using known techniques. Techniques for reconstructing segmented volumes of an anatomical feature are described in copending U.S. patent application Ser. No. 10/974,503, filed Oct. 27, 2004, titled Method and System for Focus-Adaptive Reconstruction of Spine Images; and in copending U.S. patent application Ser. No. 11/185,603, filed Jul. 20, 2005, titled Feature-Based Composing for 3D MR Angiography Images, both of which are hereby incorporated by reference herein in their entirety.